The elevator system is used for the essentially vertical transport of persons or goods over several floors of a building. For this purpose, the elevator system comprises at least one elevator car. This elevator car is guided by means of guide rails and is traversed along these guide rails by means of an elevator machine. The elevator system further comprises at least one elevator brake.
The elevator brake meets various requirements. As a rule, the elevator brake is used as a holding brake, which holds fast the elevator car during a standstill phase. Standstill phases occur when the elevator car is in a holding position and the drive motor is switched off or when the elevator system is out of operation. The elevator brake is also used as an emergency brake for braking and stopping the elevator car in the event of malfunction. Such malfunctions are for example an unexpected actuation of a door of the elevator during travel and also a defect of a critical electronic component, etc. Furthermore, elevator brakes are also used as so-called safety brakes. Safety brakes have for example the function of braking and holding the elevator car in the event of a suspension means being torn.
Depending on the nature of the requirement, the elevator brake must be brought gently into action or, for example in the event of the suspension means tearing, it must be brought very rapidly into action. The required braking power is also different depending on the requirement. For this reason, different brakes are usually incorporated in the elevator. Thus, for example, a usually electromagnetic holding brake is used with the drive together with a safety device on the elevator car. The electromagnetic holding brake is used as a holding and emergency brake and the safety device as a safety brake.
A brake used on the elevator car is known from application EP1671912 which can assume all three braking functions if required.
A further brake is known from European publication EP2058262 which on the one hand enables a controlled adjustment of a release force and which on the other hand enables rapid braking by tripping the release apparatus.
The brakes for elevators with two symmetrical actuating devices are known in the prior art, for example in U.S. Pat. No. 5,791,442, which actuating devices are each assigned to a brake lining and which are designed to move the respectively assigned brake lining towards the other brake lining if necessary and to clamp the braking strip or the brake disc between the two brake linings.
Accordingly, a problem arises of making available an elevator brake which can assume at least the three mentioned braking functions and which can be controlled in a straightforward manner.